Typical scanning probe microscopes (SPM) such as a typical atomic force microscope (AFM) only sense the probe tip position once the probe tip is in contact with the surface to be scanned. Typical SPMs image a measurement surface by applying a thin probe tip at the end of flexible cantilever to the measurement surface. With respect to FIG. 1, as the probe tip moves across the measurement surface, variations in the probe tip height are typically detected by the use of a laser beam reflected off the back of cantilever 130 that is received by optical detector 120. Cantilever 130 is typically actuated by piezoelectric actuator 110. Because optical detector 120 only senses the deflection of cantilever 130, e, and not the absolute position of the probe tip, the control feedback loop is known as an output error only loop. Typically, output signal u of controller 140 is used as an estimate of the measurement surface as shown in the block diagram of FIG. 1. This typically limits the bandwidth and accuracy of the measurement surface estimate u. Note that in FIG. 1 “C” designates the control portion of the SPM which includes optical detector 120 and controller 140 while “P” designates the plant which includes cantilever 130 and piezoelectric actuator 110. Furthermore, the laser beam reflected from cantilever 130 only falls near the center of optical detector 120 when the probe tip is interacting with measurement surface 105. When the probe tip is away from measurement surface 105, cantilever 130 is in an undeflected position. This means that the signal from optical detector 120 is independent of the probe tip height over measurement surface 105. Hence, the signal detected by optical detector 120 is not useful for probe tip position information until the probe tip is close enough to measurement surface 105 to interact with surface 105. This typically creates difficulties for fast seeks of measurement surface 105 because the speed of the approach to measurement surface 105 typically needs to be slow enough so that the approach can be stopped as soon as measurement surface 105 is detected by optical detector 120.